Re: PATCH: 5/6 [2nd try]: Add AVX support (i387 changes)

H.J. Lu
2010-03-12T17:24:54Z

On Sat, Mar 06, 2010 at 02:22:12PM -0800, H.J. Lu wrote:
> Hi,
>
> Here are i387 changes to support AVX. OK to install?
>
> Thanks.
>

Here is the updated patch. Any comments/suggestions?

Thanks.

H.J.
---
2010-03-12 H.J. Lu <hongjiu.lu@intel.com>

* i387-tdep.c: Include "i386-xstate.h".
(XSAVE_XSTATE_BV_ADDR): New.
(xsave_avxh_offset): Likewise.
(XSAVE_AVXH_ADDR): Likewise.
(i387_supply_xsave): Likewise.
(i387_collect_xsave): Likewise.

* i387-tdep.h (I387_NUM_YMM_REGS): New.
(I387_YMM0H_REGNUM): Likewise.
(I387_YMMENDH_REGNUM): Likewise.
(i387_supply_xsave): Likewise.
(i387_collect_xsave): Likewise.

diff --git a/gdb/i387-tdep.c b/gdb/i387-tdep.c
index 3fb5b56..66e2167 100644
--- a/gdb/i387-tdep.c
+++ b/gdb/i387-tdep.c
@@ -34,6 +34,7 @@

#include "i386-tdep.h"
#include "i387-tdep.h"
+#include "i386-xstate.h"

/* Print the floating point number specified by RAW. */

@@ -677,6 +678,518 @@ i387_collect_fxsave (const struct regcache *regcache, int regnum, void *fxsave)
FXSAVE_MXCSR_ADDR (regs));
}

+/* `xstate_bv' is at byte offset 512. */
+#define XSAVE_XSTATE_BV_ADDR(xsave) (xsave + 512)
+
+/* At xsave_avxh_offset[REGNUM] you'll find the offset to the location in
+ the upper 128bit of AVX register data structure used by the "xsave"
+ instruction where GDB register REGNUM is stored. */
+
+static int xsave_avxh_offset[] =
+{
+ 576 + 0 * 16, /* Upper 128bit of %ymm0 through ... */
+ 576 + 1 * 16,
+ 576 + 2 * 16,
+ 576 + 3 * 16,
+ 576 + 4 * 16,
+ 576 + 5 * 16,
+ 576 + 6 * 16,
+ 576 + 7 * 16,
+ 576 + 8 * 16,
+ 576 + 9 * 16,
+ 576 + 10 * 16,
+ 576 + 11 * 16,
+ 576 + 12 * 16,
+ 576 + 13 * 16,
+ 576 + 14 * 16,
+ 576 + 15 * 16 /* Upper 128bit of ... %ymm15 (128 bits each). */
+};
+
+#define XSAVE_AVXH_ADDR(tdep, xsave, regnum) \
+ (xsave + xsave_avxh_offset[regnum - I387_YMM0H_REGNUM (tdep)])
+
+/* Similar to i387_supply_fxsave, but use XSAVE extended state. */
+
+void
+i387_supply_xsave (struct regcache *regcache, int regnum,
+ const void *xsave)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
+ const gdb_byte *regs = xsave;
+ int i;
+ unsigned int clear_bv;
+ const gdb_byte *p;
+ enum
+ {
+ none = 0x0,
+ x87 = 0x1,
+ sse = 0x2,
+ avxh = 0x4,
+ all = x87 | sse | avxh
+ } regclass;
+
+ gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
+ gdb_assert (tdep->num_xmm_regs > 0);
+
+ if (regnum == -1)
+ regclass = all;
+ else if (regnum >= I387_YMM0H_REGNUM (tdep)
+ && regnum < I387_YMMENDH_REGNUM (tdep))
+ regclass = avxh;
+ else if (regnum >= I387_XMM0_REGNUM(tdep)
+ && regnum < I387_MXCSR_REGNUM (tdep))
+ regclass = sse;
+ else if (regnum >= I387_ST0_REGNUM (tdep)
+ && regnum < I387_FCTRL_REGNUM (tdep))
+ regclass = x87;
+ else
+ regclass = none;
+
+ if (regs != NULL && regclass != none)
+ {
+ /* Get `xstat_bv'. */
+ const gdb_byte *xstate_bv_p = XSAVE_XSTATE_BV_ADDR (regs);
+
+ /* The supported bits in `xstat_bv' are 1 byte. Clear part in
+ vector registers if its bit in xstat_bv is zero. */
+ clear_bv = (~(*xstate_bv_p)) & tdep->xcr0;
+ }
+ else
+ clear_bv = I386_XSTATE_AVX_MASK;
+
+ switch (regclass)
+ {
+ case none:
+ break;
+
+ case avxh:
+ if ((clear_bv & I386_XSTATE_AVX))
+ p = NULL;
+ else
+ p = XSAVE_AVXH_ADDR (tdep, regs, regnum);
+ regcache_raw_supply (regcache, regnum, p);
+ return;
+
+ case sse:
+ if ((clear_bv & I386_XSTATE_SSE))
+ p = NULL;
+ else
+ p = FXSAVE_ADDR (tdep, regs, regnum);
+ regcache_raw_supply (regcache, regnum, p);
+ return;
+
+ case x87:
+ if ((clear_bv & I386_XSTATE_X87))
+ p = NULL;
+ else
+ p = FXSAVE_ADDR (tdep, regs, regnum);
+ regcache_raw_supply (regcache, regnum, p);
+ return;
+
+ case all:
+ /* Hanle the upper YMM registers. */
+ if ((tdep->xcr0 & I386_XSTATE_AVX))
+ {
+ if ((clear_bv & I386_XSTATE_AVX))
+ p = NULL;
+ else
+ p = regs;
+
+ for (i = I387_YMM0H_REGNUM (tdep);
+ i < I387_YMMENDH_REGNUM (tdep); i++)
+ {
+ if (p != NULL)
+ p = XSAVE_AVXH_ADDR (tdep, regs, i);
+ regcache_raw_supply (regcache, i, p);
+ }
+ }
+
+ /* Handle the XMM registers. */
+ if ((tdep->xcr0 & I386_XSTATE_SSE))
+ {
+ if ((clear_bv & I386_XSTATE_SSE))
+ p = NULL;
+ else
+ p = regs;
+
+ for (i = I387_XMM0_REGNUM (tdep);
+ i < I387_MXCSR_REGNUM (tdep); i++)
+ {
+ if (p != NULL)
+ p = FXSAVE_ADDR (tdep, regs, i);
+ regcache_raw_supply (regcache, i, p);
+ }
+ }
+
+ /* Handle the x87 registers. */
+ if ((tdep->xcr0 & I386_XSTATE_X87))
+ {
+ if ((clear_bv & I386_XSTATE_X87))
+ p = NULL;
+ else
+ p = regs;
+
+ for (i = I387_ST0_REGNUM (tdep);
+ i < I387_FCTRL_REGNUM (tdep); i++)
+ {
+ if (p != NULL)
+ p = FXSAVE_ADDR (tdep, regs, i);
+ regcache_raw_supply (regcache, i, p);
+ }
+ }
+ break;
+ }
+
+ /* Only handle x87 control registers. */
+ for (i = I387_FCTRL_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
+ if (regnum == -1 || regnum == i)
+ {
+ if (regs == NULL)
+ {
+ regcache_raw_supply (regcache, i, NULL);
+ continue;
+ }
+
+ /* Most of the FPU control registers occupy only 16 bits in
+ the xsave extended state. Give those a special treatment. */
+ if (i != I387_FIOFF_REGNUM (tdep)
+ && i != I387_FOOFF_REGNUM (tdep))
+ {
+ gdb_byte val[4];
+
+ memcpy (val, FXSAVE_ADDR (tdep, regs, i), 2);
+ val[2] = val[3] = 0;
+ if (i == I387_FOP_REGNUM (tdep))
+ val[1] &= ((1 << 3) - 1);
+ else if (i== I387_FTAG_REGNUM (tdep))
+ {
+ /* The fxsave area contains a simplified version of
+ the tag word. We have to look at the actual 80-bit
+ FP data to recreate the traditional i387 tag word. */
+
+ unsigned long ftag = 0;
+ int fpreg;
+ int top;
+
+ top = ((FXSAVE_ADDR (tdep, regs,
+ I387_FSTAT_REGNUM (tdep)))[1] >> 3);
+ top &= 0x7;
+
+ for (fpreg = 7; fpreg >= 0; fpreg--)
+ {
+ int tag;
+
+ if (val[0] & (1 << fpreg))
+ {
+ int regnum = (fpreg + 8 - top) % 8
+ + I387_ST0_REGNUM (tdep);
+ tag = i387_tag (FXSAVE_ADDR (tdep, regs, regnum));
+ }
+ else
+ tag = 3; /* Empty */
+
+ ftag |= tag << (2 * fpreg);
+ }
+ val[0] = ftag & 0xff;
+ val[1] = (ftag >> 8) & 0xff;
+ }
+ regcache_raw_supply (regcache, i, val);
+ }
+ else
+ regcache_raw_supply (regcache, i, FXSAVE_ADDR (tdep, regs, i));
+ }
+
+ if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
+ {
+ p = regs == NULL ? NULL : FXSAVE_MXCSR_ADDR (regs);
+ regcache_raw_supply (regcache, I387_MXCSR_REGNUM (tdep), p);
+ }
+}
+
+/* Similar to i387_collect_fxsave, but use XSAVE extended state. */
+
+void
+i387_collect_xsave (const struct regcache *regcache, int regnum,
+ void *xsave, int gcore)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
+ gdb_byte *regs = xsave;
+ int i;
+ enum
+ {
+ none = 0x0,
+ check = 0x1,
+ x87 = 0x2 | check,
+ sse = 0x4 | check,
+ avxh = 0x8 | check,
+ all = x87 | sse | avxh
+ } regclass;
+
+ gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
+ gdb_assert (tdep->num_xmm_regs > 0);
+
+ if (regnum == -1)
+ regclass = all;
+ else if (regnum >= I387_YMM0H_REGNUM (tdep)
+ && regnum < I387_YMMENDH_REGNUM (tdep))
+ regclass = avxh;
+ else if (regnum >= I387_XMM0_REGNUM(tdep)
+ && regnum < I387_MXCSR_REGNUM (tdep))
+ regclass = sse;
+ else if (regnum >= I387_ST0_REGNUM (tdep)
+ && regnum < I387_FCTRL_REGNUM (tdep))
+ regclass = x87;
+ else
+ regclass = none;
+
+ if (gcore)
+ {
+ /* Update XCR0 and `xstate_bv' with XCR0 for gcore. */
+ if (tdep->xsave_xcr0_offset != -1)
+ memcpy (regs + tdep->xsave_xcr0_offset, &tdep->xcr0, 8);
+ memcpy (XSAVE_XSTATE_BV_ADDR (regs), &tdep->xcr0, 8);
+
+ switch (regclass)
+ {
+ default:
+ abort ();
+
+ case all:
+ /* Handle the upper YMM registers. */
+ if ((tdep->xcr0 & I386_XSTATE_AVX))
+ for (i = I387_YMM0H_REGNUM (tdep);
+ i < I387_YMMENDH_REGNUM (tdep); i++)
+ regcache_raw_collect (regcache, i,
+ XSAVE_AVXH_ADDR (tdep, regs, i));
+
+ /* Handle the XMM registers. */
+ if ((tdep->xcr0 & I386_XSTATE_SSE))
+ for (i = I387_XMM0_REGNUM (tdep);
+ i < I387_MXCSR_REGNUM (tdep); i++)
+ regcache_raw_collect (regcache, i,
+ FXSAVE_ADDR (tdep, regs, i));
+
+ /* Handle the x87 registers. */
+ if ((tdep->xcr0 & I386_XSTATE_X87))
+ for (i = I387_ST0_REGNUM (tdep);
+ i < I387_FCTRL_REGNUM (tdep); i++)
+ regcache_raw_collect (regcache, i,
+ FXSAVE_ADDR (tdep, regs, i));
+ break;
+
+ case x87:
+ regcache_raw_collect (regcache, regnum,
+ FXSAVE_ADDR (tdep, regs, regnum));
+ return;
+
+ case sse:
+ regcache_raw_collect (regcache, regnum,
+ FXSAVE_ADDR (tdep, regs, regnum));
+ return;
+
+ case avxh:
+ regcache_raw_collect (regcache, regnum,
+ XSAVE_AVXH_ADDR (tdep, regs, regnum));
+ return;
+ }
+ }
+ else
+ {
+ if ((regclass & check))
+ {
+ gdb_byte raw[I386_MAX_REGISTER_SIZE];
+ gdb_byte *xstate_bv_p = XSAVE_XSTATE_BV_ADDR (regs);
+ unsigned int xstate_bv = 0;
+ /* The supported bits in `xstat_bv' are 1 byte. */
+ unsigned int clear_bv = (~(*xstate_bv_p)) & tdep->xcr0;
+ gdb_byte *p;
+
+ /* Clear register set if its bit in xstat_bv is zero. */
+ if (clear_bv)
+ {
+ if ((clear_bv & I386_XSTATE_AVX))
+ for (i = I387_YMM0H_REGNUM (tdep);
+ i < I387_YMMENDH_REGNUM (tdep); i++)
+ memset (XSAVE_AVXH_ADDR (tdep, regs, i), 0, 16);
+
+ if ((clear_bv & I386_XSTATE_SSE))
+ for (i = I387_XMM0_REGNUM (tdep);
+ i < I387_MXCSR_REGNUM (tdep); i++)
+ memset (FXSAVE_ADDR (tdep, regs, i), 0, 16);
+
+ if ((clear_bv & I386_XSTATE_X87))
+ for (i = I387_ST0_REGNUM (tdep);
+ i < I387_FCTRL_REGNUM (tdep); i++)
+ memset (FXSAVE_ADDR (tdep, regs, i), 0, 10);
+ }
+
+ if (regclass == all)
+ {
+ /* Check if any upper YMM registers are changed. */
+ if ((tdep->xcr0 & I386_XSTATE_AVX))
+ for (i = I387_YMM0H_REGNUM (tdep);
+ i < I387_YMMENDH_REGNUM (tdep); i++)
+ {
+ regcache_raw_collect (regcache, i, raw);
+ p = XSAVE_AVXH_ADDR (tdep, regs, i);
+ if (memcmp (raw, p, 16))
+ {
+ xstate_bv |= I386_XSTATE_AVX;
+ memcpy (p, raw, 16);
+ }
+ }
+
+ /* Check if any SSE registers are changed. */
+ if ((tdep->xcr0 & I386_XSTATE_SSE))
+ for (i = I387_XMM0_REGNUM (tdep);
+ i < I387_MXCSR_REGNUM (tdep); i++)
+ {
+ regcache_raw_collect (regcache, i, raw);
+ p = FXSAVE_ADDR (tdep, regs, i);
+ if (memcmp (raw, p, 16))
+ {
+ xstate_bv |= I386_XSTATE_SSE;
+ memcpy (p, raw, 16);
+ }
+ }
+
+ /* Check if any X87 registers are changed. */
+ if ((tdep->xcr0 & I386_XSTATE_X87))
+ for (i = I387_ST0_REGNUM (tdep);
+ i < I387_FCTRL_REGNUM (tdep); i++)
+ {
+ regcache_raw_collect (regcache, i, raw);
+ p = FXSAVE_ADDR (tdep, regs, i);
+ if (memcmp (raw, p, 10))
+ {
+ xstate_bv |= I386_XSTATE_X87;
+ memcpy (p, raw, 10);
+ }
+ }
+ }
+ else
+ {
+ /* Check if REGNUM is changed. */
+ regcache_raw_collect (regcache, regnum, raw);
+
+ switch (regclass)
+ {
+ default:
+ abort ();
+
+ case avxh:
+ /* This is an upper YMM register. */
+ p = XSAVE_AVXH_ADDR (tdep, regs, regnum);
+ if (memcmp (raw, p, 16))
+ {
+ xstate_bv |= I386_XSTATE_AVX;
+ memcpy (p, raw, 16);
+ }
+ break;
+
+ case sse:
+ /* This is an SSE register. */
+ p = FXSAVE_ADDR (tdep, regs, regnum);
+ if (memcmp (raw, p, 16))
+ {
+ xstate_bv |= I386_XSTATE_SSE;
+ memcpy (p, raw, 16);
+ }
+ break;
+
+ case x87:
+ /* This is an x87 register. */
+ p = FXSAVE_ADDR (tdep, regs, regnum);
+ if (memcmp (raw, p, 10))
+ {
+ xstate_bv |= I386_XSTATE_X87;
+ memcpy (p, raw, 10);
+ }
+ break;
+ }
+ }
+
+ /* Update the corresponding bits in `xstate_bv' if any SSE/AVX
+ registers are changed. */
+ if (xstate_bv)
+ {
+ /* The supported bits in `xstat_bv' are 1 byte. */
+ *xstate_bv_p |= (gdb_byte) xstate_bv;
+
+ switch (regclass)
+ {
+ default:
+ abort ();
+
+ case all:
+ break;
+
+ case x87:
+ case sse:
+ case avxh:
+ /* Register REGNUM has been updated. Return. */
+ return;
+ }
+ }
+ else
+ {
+ /* Return if REGNUM isn't changed. */
+ if (regclass != all)
+ return;
+ }
+ }
+ }
+
+ /* Only handle x87 control registers. */
+ for (i = I387_FCTRL_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
+ if (regnum == -1 || regnum == i)
+ {
+ /* Most of the FPU control registers occupy only 16 bits in
+ the xsave extended state. Give those a special treatment. */
+ if (i != I387_FIOFF_REGNUM (tdep)
+ && i != I387_FOOFF_REGNUM (tdep))
+ {
+ gdb_byte buf[4];
+
+ regcache_raw_collect (regcache, i, buf);
+
+ if (i == I387_FOP_REGNUM (tdep))
+ {
+ /* The opcode occupies only 11 bits. Make sure we
+ don't touch the other bits. */
+ buf[1] &= ((1 << 3) - 1);
+ buf[1] |= ((FXSAVE_ADDR (tdep, regs, i))[1] & ~((1 << 3) - 1));
+ }
+ else if (i == I387_FTAG_REGNUM (tdep))
+ {
+ /* Converting back is much easier. */
+
+ unsigned short ftag;
+ int fpreg;
+
+ ftag = (buf[1] << 8) | buf[0];
+ buf[0] = 0;
+ buf[1] = 0;
+
+ for (fpreg = 7; fpreg >= 0; fpreg--)
+ {
+ int tag = (ftag >> (fpreg * 2)) & 3;
+
+ if (tag != 3)
+ buf[0] |= (1 << fpreg);
+ }
+ }
+ memcpy (FXSAVE_ADDR (tdep, regs, i), buf, 2);
+ }
+ else
+ regcache_raw_collect (regcache, i, FXSAVE_ADDR (tdep, regs, i));
+ }
+
+ if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
+ regcache_raw_collect (regcache, I387_MXCSR_REGNUM (tdep),
+ FXSAVE_MXCSR_ADDR (regs));
+}
+
/* Recreate the FTW (tag word) valid bits from the 80-bit FP data in
*RAW. */

diff --git a/gdb/i387-tdep.h b/gdb/i387-tdep.h
index 645eb91..976fa11 100644
--- a/gdb/i387-tdep.h
+++ b/gdb/i387-tdep.h
@@ -33,6 +33,8 @@ struct ui_file;
#define I387_ST0_REGNUM(tdep) ((tdep)->st0_regnum)
#define I387_NUM_XMM_REGS(tdep) ((tdep)->num_xmm_regs)
#define I387_MM0_REGNUM(tdep) ((tdep)->mm0_regnum)
+#define I387_NUM_YMM_REGS(tdep) ((tdep)->num_ymm_regs)
+#define I387_YMM0H_REGNUM(tdep) ((tdep)->ymm0h_regnum)

#define I387_FCTRL_REGNUM(tdep) (I387_ST0_REGNUM (tdep) + 8)
#define I387_FSTAT_REGNUM(tdep) (I387_FCTRL_REGNUM (tdep) + 1)
@@ -45,6 +47,8 @@ struct ui_file;
#define I387_XMM0_REGNUM(tdep) (I387_ST0_REGNUM (tdep) + 16)
#define I387_MXCSR_REGNUM(tdep) \
(I387_XMM0_REGNUM (tdep) + I387_NUM_XMM_REGS (tdep))
+#define I387_YMMENDH_REGNUM(tdep) \
+ (I387_YMM0H_REGNUM (tdep) + I387_NUM_YMM_REGS (tdep))

/* Print out the i387 floating point state. */

@@ -99,6 +103,11 @@ extern void i387_collect_fsave (const struct regcache *regcache, int regnum,
extern void i387_supply_fxsave (struct regcache *regcache, int regnum,
const void *fxsave);

+/* Similar to i387_supply_fxsave, but use XSAVE extended state. */
+
+extern void i387_supply_xsave (struct regcache *regcache, int regnum,
+ const void *xsave);
+
/* Fill register REGNUM (if it is a floating-point or SSE register) in
*FXSAVE with the value from REGCACHE. If REGNUM is -1, do this for
all registers. This function doesn't touch any of the reserved
@@ -107,6 +116,11 @@ extern void i387_supply_fxsave (struct regcache *regcache, int regnum,
extern void i387_collect_fxsave (const struct regcache *regcache, int regnum,
void *fxsave);

+/* Similar to i387_collect_fxsave, but use XSAVE extended state. */
+
+extern void i387_collect_xsave (const struct regcache *regcache,
+ int regnum, void *xsave, int gcore);
+
/* Prepare the FPU stack in REGCACHE for a function return. */

extern void i387_return_value (struct gdbarch *gdbarch,